A large mass of demonstrators gathered in Pasadena to protest the officers involved in a confrontation that led to the death of a man, as police release the 911 calls and surveillance video of the incident. Jane Yamamoto and Beverly White report for the NBC4 News at 11 p.m. on Friday, Sept. 30, 2016. (Published Saturday, Oct. 1, 2016)

A large crowd of demonstrators shut down the streets of Pasadena on Friday, as police release the 911 calls and surveillance video in the incident of a man who died after a confrontation with officers.

The protesters, many carrying signs, marched on streets, bringing traffic to a halt at some intersections in Old Town Pasadena.

Then they received a second call around 2:35 a.m., and were told that a man had a knife and a fire extinguisher. Authorities said the caller identified the man, and that they heard a struggle during the call.

Although investigators do not know who made the calls, they believe both were made by the same person. Katz noted detectives were working to identify who that caller was.

Police were able to trace the second call to an apartment, and responded to the 200 block of East Orange Grove Boulevard in Pasadena, according to authorities.

When Pasadena police officers arrived, they attempted to detain Thomas to take him into custody, and "he struggled with the officers," Katz said. Police used a Taser and non-lethal force, and restrained him with handcuffs and ankle restraints.

Surveillance video from the complex shows officers rushing across the courtyard of the apartment where Thomas was visiting his family.

Officers noticed Thomas was no longer breathing and removed all of his restraints and started performing CPR, according to authorities. Pasadena Fire paramedics "took over life saving efforts," before Thomas eventually died, Katz said.

Lindsey believes officers used excessive force on her boyfriend, who she says was mentally ill.

"They knew he was disabled, they knew he was bipolar, they knew he was on social security, and they still killed him," she said.

Lindsey said Thomas called police claiming someone was in their apartment, and said he was holding a knife in one hand and a fire extinguisher in the other when police arrived.

Officers told him to drop both items and used a Taser twice when he did not, according to Lindsey. Then, Thomas got up and slammed the door on the officers.

"They busted through the door and they wrestled him down to the ground, they started kicking him and beating him with the stick, and then they start tying him up," Lindsey said. "And that was it, and they told us to get out."

Los Angeles County Sheriff investigators are investigating the circumstances of his death, and Katz noted that there were six detectives at the scene Friday around 11 a.m., adding that the investigation was in its "infancy."

Two officers were also injured during the confrontation, Katz said.

Police had not identified the man as of 12:30 p.m. Friday.

Anyone with information about this investigation was encouraged to call the Los Angeles Sheriff's Department's Information Bureau at 213-229-1700.